Clamping device for electron tubes and the like



May 2, 1959 J. R. SHONNARD ETAL 2,505,840

CLAMPING DEVICE FOR ELECTRON TUBES AND THE LIKE Filed April 1-3, 1949AAAA FIG. 3. FIG. 5.

AAAAAAAAAAA A \mummmxmm MW vvvvvvvvvvvvvvvvvvv AAAYAAAA IN V EN TORSJOHN R. Sf/OlV/VARD Y JOSEPH SC/IAUER A rro/PA/Ey i 'atented May 2, 1950CLAMPING DEVICE FOR ELECTRON TUBES AND THE LIKE John R. Shonnard, NewYork, N. Y., and Joseph Schauer, Cliffwood Beach, N. J., assignors toTimes Facsimile Corporation, New York, N. Y.,

a corporation of New York Application April 13, 1949, Serial No. 87,222

4 Claims. 1

This invention relates to clamping devices, and more especially itrelates to devices for clamping in place, replaceable electric units ofthe plug-in type.

A principal object of the invention is to provide an improved andsimplified clamp for holding electron tubes and the like in theirplug-in sockets, so that they are incapable of being loosened by shocks,jars or vibrations.

A feature of the invention relates to a clamp which is so constructedthat such devices as electron tubes can be readily replaced and clampedin their socket receptacles without requiring special tools such aswrenches or screwdrivers to release the clamp.

Another feature relates to an electron tube clamp which can be slidablyadjusted in a vertical direction and locked in a definite verticalposition without the use of thumb screws, set screws, or the like, whichtend to become loose after continued vibration of the parts.

A still further feature relates to the novel organization, arrangementand relative location of parts which cooperate to provide an improvedclamping arrangement for electron tubes and similar units which arearranged to be plugged into a receptacle or socket.

Other features and advantages not specifically enumerated will beapparent after a consideration of the following detailed descriptionsand the appended claims.

In the drawings, which show, by way of example, certain preferredembodiments,

Fig. l is a view, in elevation, and partly sectional, showing the clamparrangement according to the invention.

Fig. 2 is a perspective view of one of the clamp members of Fig. 1.

Fig. 3 is a view of part of Fig. 1, showing the clamp elements inreleased relation.

Fig. 4 is a top plan view of Fig. 1.

Fig. 5 is a view similar to that of Fig. 1, but showing a modificationof the clamp.

Fig. 6 is a view, in elevation, of a further modification of the clamp.

In Fig. 1, there is shown by way of example, a typical plug-in devicesuch for example as a radio tube I, carrying the usual base 2 that isprovided with the usual contact prongs (not shown), whereby the tube canbe plugged into a socket or receptacle 3 carried by chassis 4. Tofacilitate the plugging in and out of the tube, the socket 3 is usuallyof the spring contact type, the contact springs of which frictionallyengage the pins carried by the base 2. However it very frequentlyhappens that the tube may become loose in its socket, preventing theproper electrical contact between the tube elements and the associatedcircuits. There is disclosed in U. S. Patent No. 2,461,198 a clampingarrangement which overcomes the objectionable features of the usual typeof clamp which requires set screws or thumb screws to look the clampelehents in position. The present invention is in the nature of animprovement on the type of clamp disclosed in said patent.

Referring to the drawing, the clamp comprises in general, a pedestal orrod 5 which is arranged to be fastened in any suitable manner, forexample by nuts 6, l, engaging opposite sides of chassis i. If desired,the rod 5 can be riveted or permanently attached to chassis 4. In anycase, it is anchored to the chassis at a point adjacent the socket 3.Arranged to be vertically adjusted and locked to rod 5, is a clampmember 8 of springy sheet metal or alloy, such for example as aberyllium-copper alloy. It comprises a cap portion 9 which ispreferably, although not necessarily, of circular shape and providedwith a central opening I 0. Preferably, the inner margin ll of the capopening is struck-up so as to form a tapered rim which may conform tothe curved top [2 of tube l.

The flat rim Id of cap 9 has an arm l3 which is bent downwardly to forma U-shaped portion i5 comprising substantially parallel side walls It,ii, and bottom wall 3. The side wall I! terminates in a bent end portion[9 which forms a finger pressure lug for unlocking the clamp, asv

will be described hereinbelow. The U-shaped portion 55 is provided witha slot 20 which extends the full length of wall [6, and also ex tendsalong the arm l3 a distance which is slightly greater than the diameterof rod 5. Like-" wise, the slot 20 extends along the bottom l8 adistance which is slightly greater than the diameter of rod 5. The slot20 has a width which is slightly greater than the diameter of rod 5, asshown in Fig. 4. Preferably, the end edges 2|, 22, of the slot arerounded to conform to the curvature of rod 5. It will be understood, ofcourse, that the rod 5 is not necessarily of round cross-section, andmay be of any desired crossseotional shape, but has its surface grooved,threaded, or otherwise roughened, so as to form an interlock with theedges 2| and 22 when the member 8 is in clamping relation with the tubeI. as will be described hereinbelow.

In the normal or untensed condition of memher 8, the arm I3 is atslightly less than with respect to wall it, as represented by the dottedline position of Fig. 1. In this condition, the horizontal distancebetween the end edges 21 and 22 of slot 26 are just sufiicient to allowthe rod 5 to pass freely through the vertically aligned end sections ofslot 20, until the cap 9 engages the top of tube I. Then by pressingdownwardly on portion l3, as indicated by the arrow A, the efiectivehorizontal distance between the slot ends 2!, 22, is decreased, causingthese ends firmly to grip the opposite sides of rod 5, as shown inFig. 1. Thus the member 8 resiliently and firmly presses downwardly uponthe tube l, and at the same time the ends 2! and'22 of the slot 20 arefirmly interlocked with the opposite sides of rod 5.

When it is desired to release the clamp, it is merely necessary to pressupon the lug I9, as indicated by the arrow B. As a result of thispressure, the horizontal distance between the ends 2i. and 22 of slot225! is increased, as shown in Fig, 3, thus providing a clear passagefor the rod 5 with respect to the slot. 283. In other words, the, arm 63moves slightly in the direction of the arrow C, and the bottom l8 movesslightly in the direction of the arrow D, as shown in Fig. 3. It shouldbe observed that this pressure releases both ends 2! and 22, fromengagement with the rod 5 and the clamp, can be easily raised andlowered while maintaining the pressure on lug I9.

In some cases the clamp may be required for 5.12 in clampingmetal units,such for example as can-type electrolytic condensers and the like, suchas represented by the device 23 (Fig. 5).

In that event, the cap member 9 may have attached to its under surfacean insulator sheet or washer 24 b means of rivets 25, or the like, thuseffectively electrically insulating the metal body of the clamp member 8from the metal casing or can of the device 23.

It will be understood, of course, that the in,- ventiQ is not limited tothe fabrication of the member 8. from a single, strip or sheet ofspringy metal. Thus as shown in Fig. 6, the cap 9 can be made as aseparate unit and attached to the arm lj3 by suitable rivets '26, or thelike.

'While certain particular embodiments have been disclosed herein, itwill be understood that changes and modifications may be made thereinwithout departing from the spirit and scope of the invention.

What is claimed is:

1'. A clamp for a plug-in unit such as an elec-, tron tube and the like,comprising a fiexiblemetal blank carrying at one end a portion arrangedto engage the top of the unit to be clamped, said blank having anotherportion bent back on itself and having a continuous slot therein withthe end portions of the slot in spaced alignment to receive a rod, saidslot having its length correlated with the thickness of said rod tocause at least one of the slot ends to tightly engage the surface ofsaid rod.

2. A clamp for a plug-in unit such as an electron tube and the like,comprising a flexible metal strip carrying at one end a portion forengagement with the top of the unit to be clamped, a rod to. which saidstrip is releasably locked, said strip having a slot to receive said rodand being bent back to bring the end portions of said slot into spacedvertical alignment and with the horizontal distance between the slotends approximately the same as the thickness of said rod when one end ofsaid slot is in interlocking engagement with the surface of said rod.

3. A clamp for a plug-in unit such as an electron tube or the like,comprising a flexible metal strip carrying at one end a capfor engagingthe unit to be clamped, said strip having a portion bent to asubstantial U shape, said portion having a slot with the ends of theslot in spaced vertical alignment, an anchoring rod passing through saidaligned slot ends and maintained in locking engagement with the ends ofthe slot by reason of the flexible engagement between said cap and thetop of said unit.

4. A member for clamping an electric unit such as an electron tube orthe like, comprising a metal strip having a substantially straight part,and another part doubly bent back to form a section having substantiallyparallel spaced, side, walls joined by a bottom wall, said straight partcarrying at one end a cap to engage the top of said unitQa slotextending along the length of one side wall of said bent, section andhaving one end portion partially extending along said straight part ofthe strip, said slot having its.

. opposite end portion extending along the said bottom wall, saidstraight part of'the strip being bent with respect to said one of saidside walls to bring the ends of said, slot into substantial verticalalignment to interlock with an anchoring post passing therethrough.

JOHN R. SHONNARD. JOSEPH SCHAUER.

REFERENCES CITED.

The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,326,903 Tinnerman Aug. 1'7,1943 2,446,564 Vezzosi Aug. 10, 1,948 2,461,198 Chiger Feb. 8, 1949

